DESCRIPTION ( provided by applicant): This application is for renewal of a training program directed by Louis Hersh and co-directed by Linda Dwoskin and Sharon Walsh. We request continued support for four predoctoral and two postdoctoral trainees utilizing a training faculty of 15 housed in three colleges and 5 different departments within the University of Kentucky. All of the training faculty have been funded through NIDA or collaborate with NIDA funding training faculty with their research broadly focused on the molecular aspects of drug abuse. The University of Kentucky has a long history of involvement in drug abuse research and includes the Center on Drug and Alcohol Research and the Center for Drug and Alcohol Research and Translation. The goal of this training program continues to be the preparation of promising graduate students and postdoctoral fellows for careers in drug abuse research. The program provides broad-based training in modern aspects of drug abuse research with a particular emphasis on studying the cellular and molecular aspects of receptors involved in the response to drugs and the development of ligands which interact with these receptors as potential pharmacotherapy's for drug abuse. The training faculty share a common interest in understanding basic mechanisms related to drug abuse at the molecular level. The emphasis of the training faculty focus on the structure of opiate receptor ligands, the effects of opiate receptor ligands on physiological processes, and the structure and function of the proteins and ligands involved in opiate receptors. Trainees learn from a strong faculty who utilize state-of-the-art methodological approaches to drug abuse research. A unique aspect of this program is the interaction of trainees with other faculty and trainees involved in the behavioral aspects of drug abuse, giving them a broad based understanding of drug abuse research. This unique training opportunity is hoped to fill the need for new investigators in drug abuse research who have a broad understanding of the field.